The transit ends at 11:04 a.m., when Mercury finishes crossing the sun and disappears from view.
Mercury's trek across the Sun begins at 4:35 a.m. PST (7:35 a.m. EST), meaning viewers on the East Coast of the USA can experience the entire event, as the Sun will have already risen before the transit begins. Africa, Europe, and western Asia will be able to see it at Monday's sunset. This could be done by having observers at distant points on Earth look at the variation in a planet's apparent position against the disk of the Sun - a phenomenon known as parallax shift. Eastern time. And while you won't be able see it without protective glasses and heavy-duty telescope equipment, there are still plenty of ways to enjoy the show.
In the early 1600s, Johannes Kepler discovered that both Mercury and Venus would transit the Sun in 1631.
Transits occur when planets come between us and the Sun, meaning that only two planets can transit: Venus and Mercury. Witnessing a transit is all a matter of timing.
Future transits of Mercury will happen in November of 2032, November of 2039, and May of 2049, but only the 2049 event will be observable from Santa Barbara. One team used the transits to indirectly calculate the effect of tidal forces of the Moon on Earth.
Again, you'll need proper eye protection for Monday's spectacle: Telescopes or binoculars with solar filters are recommended. Earthlings get treated to just 13 or 14 Mercury transits a century.
The Curiosity rover on Mars observed the planet Mercury transiting the Sun in 2014, the first time a planetary transit was seen from a celestial body other than the Earth. That knowledge is valuable to astronomers hoping to use the transit method to spot exoplanets around distant stars.
Since Mercury blocks out a tiny part of the light from the Sun, it should not be seen using the pinhole projectors that worked successfully in the solar eclipse in March 2015, or by using "eclipse glasses" with solar filters. The last transit of Venus was in June of 2012, and the next will occur in December of 2117.